Heat dissipation system and method for energy storage battery pack

Abstract

The invention belongs to the technical field of heat management of energy storage batteries, particularly relates to a heat dissipation system and method for an energy storage battery pack, and aims to solve the problem that local hot spots randomly appearing in the battery pack cannot be dynamically, directionally and accurately dissipated in the conventional air cooling, liquid cooling and simple combined heat dissipation modes. The system comprises a heat dissipation cabin, a driving mechanism, a liquid cooling assembly, an air cooling assembly, a temperature sensing module, a battery heat dissipation main control module and an execution control module. And a liquid cooling flow channel and an air cooling flow channel with an adjustable air deflector are arranged in the heat dissipation cabin. The temperature sensing module collects the high-risk area in the battery pack, the inlet and outlet of the liquid cooling plate and the environment temperature. And the battery heat dissipation main control module identifies the hot spot area and determines a heat dissipation strategy. And the execution control module dynamically and cooperatively adjusts the rotating speed of the fan, the flow of the liquid cooling circulating pump and the deflection angle of the air deflector according to the strategy, so that on-demand directional distribution of the cooling capacity is realized, local hot spots are effectively eliminated, and the heat dissipation efficiency and the system safety are improved.

Description

Technical Field

[0001] This invention belongs to the field of thermal management technology for energy storage batteries, and specifically relates to a heat dissipation system and method for an energy storage battery pack. Background Technology

[0002] With the increasing global emphasis on environmental protection and sustainable development, lithium-ion batteries have become one of the most mainstream battery technologies in energy storage power stations due to their advantages such as high energy density, long cycle life, and high charge and discharge efficiency. Especially in scenarios requiring rapid response, high energy density, and long service life, such as grid peak shaving and frequency regulation, distributed energy storage, and industrial and commercial energy storage, lithium-ion battery packs are widely used. The main components of a lithium-ion battery pack include: (1) a battery module composed of series and parallel connections of battery cells, including the central battery cell of the module and the top cover terminals of the battery cells. (2) High-voltage electrical connection components: including busbars, tabs, and high current transmission paths such as crimping or welding interfaces.

[0003] However, under continuous charging and discharging, extreme environmental conditions, and high-density cluster operation, battery packs are prone to forming "hot spots" due to localized heat accumulation. If the temperature of the hot spot exceeds the optimal operating range of 25°C to 40°C or the temperature difference within the pack is greater than 5°C, it will quickly lead to battery performance degradation, shortened cycle life, and even trigger thermal runaway safety accidents. Therefore, efficient thermal management with "eliminating hot spots" as the core has become a key bottleneck for the safe and stable operation of energy storage power stations.

[0004] Currently, battery thermal management mainly employs air cooling, liquid cooling, or a simple combination of both. These heat dissipation methods lack sufficient cooling capacity and cannot dynamically, directionally, and precisely dissipate localized hot spots that randomly appear inside the battery pack or are located in areas with weak heat exchange. For example, while air cooling systems are simple in structure and low in cost, the airflow organization during the heat exchange process is difficult to control precisely, failing to effectively solve the problem of localized overheating inside the battery pack, especially in areas where airflow is difficult to reach, such as the bottom and middle sections. As another example, liquid cooling systems achieve high efficiency through heat exchange between the coolant and the cold plate, but the flow path of its cooling pipes (usually serpentine) remains fixed after installation. This "fixed water path" has inherent defects: flow dead zones or weak heat exchange areas are easily formed at bends and abrupt changes in the flow path. When a battery cell abnormally heats up near such areas, the liquid cooling system, due to its fixed path and delayed response, cannot promptly and effectively suppress the "hot spot." Existing air-cooling and liquid-cooling combination systems mostly mechanically superimpose the two cooling methods, failing to dynamically and precisely direct cooling capacity to the weakest areas requiring heat dissipation based on the actual temperature field distribution inside the battery pack. This results in high energy consumption when pursuing cooling efficiency, and inability to provide dynamic, directional, and precise heat dissipation in the face of sudden localized thermal runaway risks. Consequently, the system suffers from slow response times, insufficient safety redundancy, and difficulty in ensuring the safety, efficiency, and stability of the energy storage power station's battery pack.

[0005] Therefore, there is an urgent need for a heat dissipation system and method for energy storage battery packs that can overcome the limitations of fixed water channels and achieve on-demand, directional, and precise allocation of cooling capacity. Summary of the Invention

[0006] To address the problems existing in the prior art, the purpose of this invention is to provide a heat dissipation system and method for energy storage battery packs, which enables dynamic, directional, and precise enhanced heat dissipation of local hot spots that randomly appear inside the battery pack or are located in areas with weak heat exchange, significantly improving heat dissipation efficiency, temperature uniformity, and system safety redundancy.

[0007] The technical solution of this invention is: A heat dissipation system for an energy storage battery pack includes a heat dissipation chamber for housing the battery pack, and further includes: The liquid cooling assembly includes a liquid cooling circulation pump, a liquid cooling plate, and a liquid cooling channel coiled in a serpentine pattern inside the liquid cooling plate. The liquid cooling plate is located near and fixed to the top or bottom wall of the heat dissipation chamber, and one side of it is designed to contact the battery pack. The outlet of the liquid cooling circulation pump is connected to the inlet of the liquid cooling channel, and the inlet of the liquid cooling circulation pump is connected to the outlet of the liquid cooling channel, forming a coolant circulation loop. The air-cooled assembly includes fans, air guide plates, and drive mechanisms. There are at least three fans, which are fixed on three continuous side walls of the heat dissipation chamber. Two fans are arranged opposite each other to supply air into the heat dissipation chamber, and the other fan is used to exhaust hot air from the heat dissipation chamber. The three fans form a dual-inlet, single-outlet air-cooling channel in the heat dissipation chamber. The air-cooling channel is used to connect with the air duct that runs through the battery pack casing. Two sets of air guide plate arrays are respectively arranged on the side of the air-cooling channel near the two fans used for supplying air. Each set of air guide plate arrays is equipped with a drive mechanism corresponding to it. The drive mechanism is fixed on the heat dissipation chamber. The output end of each drive mechanism is connected to each air guide plate in the corresponding air guide plate array to adjust the angle of the air guide plate. The intelligent control unit includes a temperature sensing module, a battery heat dissipation main control module, and an execution control module, which are electrically connected in sequence. The temperature sensing module is used to collect the temperature of multiple high-risk areas within the battery pack, the inlet and outlet temperatures of the liquid cooling medium within the liquid cooling plate, and the ambient temperature. The battery heat dissipation main control module is used to identify hot spots and determine heat dissipation control strategies based on the high-risk area temperatures, the inlet and outlet temperatures of the liquid cooling medium within the liquid cooling plate, and the ambient temperature. The execution control module is electrically connected to the drive mechanism, the liquid cooling circulation pump, and the fan, and is used to dynamically adjust the fan speed, the liquid cooling circulation pump flow rate, and the air guide plate angle according to the heat dissipation control strategy to achieve directional heat dissipation.

[0008] Preferably, a heat dissipation fin array is fixed between the liquid cooling plate and the bottom or top wall of the heat dissipation chamber, and the liquid cooling plate is in contact with the heat dissipation fin array.

[0009] Preferably, the temperature sensing module includes: Multiple hotspot temperature sensors are arranged next to the terminal posts of the cell top cover, the side of the cell in the center of the module, the bus crimping interface, and the root of the tab in the battery pack to collect the temperature of multiple high-risk areas in the battery pack. The air duct temperature sensor is installed at the air inlet and air outlet of the air-cooled flow channel to monitor the air inlet temperature and exhaust temperature of the air-cooled flow channel. The air inlet temperature is also used to characterize the ambient temperature. Liquid cooling temperature sensors are placed at the inlet and outlet of the liquid cooling plate to collect the inlet and outlet temperatures of the liquid cooling medium on the liquid cooling plate.

[0010] Preferably, the battery heat dissipation main control module includes a hot spot identification unit, which is used to determine that the area corresponding to any of the temperature measuring terminals is a hot spot area when the temperature value collected by any of the temperature measuring terminals is ≥38℃ or its temperature rise rate is ≥0.05℃ / s, and to lock the hot spot coordinates according to the spatial position relationship of the sensors.

[0011] Preferably, the battery heat dissipation main control module includes a graded operating condition control unit, which is used to perform the following operations: Level 1 operating condition: When the battery pack reaches its highest temperature T max When the temperature is ≤35℃ and the temperature difference between the inlet and outlet of the liquid cooling medium on the liquid cooling plate is <3℃, the liquid cooling circulation pump is controlled to be shut down or put into standby mode, and the fan is controlled to run at the rated speed with a duty cycle of not less than 30%. Level 2 operating condition: When 35℃ ≤ maximum battery pack temperature T max When the temperature of the liquid cooling medium is ≤45℃ and the temperature difference between the inlet and outlet of the liquid cooling plate is ≤5℃, the liquid cooling circulating pump is controlled to operate at the rated flow rate with a flow control signal duty cycle of not less than 50%, and the fan is controlled to operate at the rated speed with a speed duty cycle of not less than 50%. Level 3 operating condition: When the battery pack reaches its highest temperature T max When the temperature is ≥45℃ and the temperature difference between the inlet and outlet of the liquid cooling medium is ≥5℃, the fan is controlled to run at full speed and the liquid cooling circulation pump is controlled to run at full flow. Among them, the highest temperature of the battery pack T max This refers to the maximum temperature collected in real time by multiple hotspot temperature sensors deployed within the battery pack.

[0012] Preferably, the fan speed and the liquid-cooled circulating pump flow rate are determined according to the following formulas: Fan speed regulation formula: , in, The duty cycle represents the fan speed. The value range is 30% to 100%; Ambient temperature; This is the highest temperature of the battery pack, which is the maximum temperature collected in real time by multiple hot spot temperature sensors deployed inside the battery pack. The environmental temperature regulation weighting coefficient has a value range of 0.5% / ℃ to 2% / ℃. The formula for regulating the flow rate of a liquid-cooled circulating pump is as follows: , in, Duty cycle of the flow control signal for the liquid-cooled circulating pump; This refers to the liquid inlet temperature of the liquid cooling plate. This refers to the liquid outlet temperature of the liquid cooling plate.

[0013] Preferably, the system also includes a sensor fault compensation module, which, when any temperature sensor in the temperature sensing module fails, performs temperature estimation based on the temperature data of the effective temperature sensor adjacent to the failed temperature sensor, as well as the current deflection angle of the air guide plate and the inlet and outlet temperatures of the liquid cooling medium on the liquid cooling plate, in order to compensate for the temperature data of the failed temperature sensor and continue to execute the heat dissipation control strategy.

[0014] A heat dissipation method for an energy storage battery pack, implemented using any of the systems described above, includes the following steps: The temperature sensing module collects the temperature of high-risk areas inside the battery pack, the temperature of the liquid cooling medium entering and exiting the liquid cooling plate, and the ambient temperature. Based on the temperature of high-risk areas within the battery pack, the distribution of hotspot areas in the battery pack is determined, and their spatial locations are pinpointed. Based on the highest temperature of all hot spots in the battery pack and the temperature difference between the inlet and outlet of the liquid cooling medium on the liquid cooling plate, a heat dissipation control strategy is determined. Based on the heat dissipation control strategy, the fan, liquid cooling circulation pump, and drive mechanism are started to dynamically adjust the fan speed, liquid cooling circulation pump flow rate, and air guide plate angle. When the identified hot spot area appears in a local location of the battery pack, the current liquid cooling circulation pump flow rate is maintained, the fan is controlled to run at a preset speed, and the angle of the air guide plates on both sides of the air cooling channel is adjusted to form an asymmetric airflow field, which directs the cooling airflow to the hot spot area to complete the directional heat dissipation of the battery pack.

[0015] Preferably, it also includes a predictive control step: based on the current temperature and temperature rise rate of the hotspot area, predicting future... The temperature after a certain time is determined, and the threshold for the operating condition classification is dynamically adjusted or the enhanced heat dissipation action is triggered in advance based on the predicted temperature, wherein the predicted temperature is determined according to the following formula: , in, To predict temperature; The current temperature of the hotspot area; This is the preset prediction time step.

[0016] Preferably, the method for adjusting the angle of the air guide plate is as follows: For a single hotspot area, the deflection angle of the air guide plate is determined according to the following formula: , in, This refers to the deflection angle of the air guide plate; This represents the maximum temperature in the corresponding hotspot area; For multiple hot spots, the deflection angle of the air guide plate is the weighted average of the deflection angles of the air guide plate calculated for each hot spot; wherein, the weight of each hot spot is proportional to the square of the difference between its temperature and a preset threshold.

[0017] Compared with the prior art, the energy storage battery pack heat dissipation system and method of the present invention have the following advantages: This invention uses a temperature sensing module to collect real-time data on the temperatures of multiple high-risk areas within the battery pack, as well as the temperature of the liquid cooling medium and the ambient temperature. The battery heat dissipation main control module identifies hot spots and determines the heat dissipation control strategy. Then, through the execution control module, it dynamically and collaboratively adjusts the fan speed, liquid cooling circulation pump flow rate, and the angle of the adjustable air guide plate in the air cooling channel. This organically integrates and intelligently distributes the air cooling airflow organization and the fixed liquid cooling water channel within the heat dissipation chamber. The system can dynamically adjust the overall cooling intensity and precisely control the airflow direction based on the real and random temperature field changes inside the battery pack. In particular, for the heat exchange weak areas caused by the fixed liquid cooling channel, the air guide plate can form an asymmetric airflow field to guide the cooling airflow to the local hot spots. This system effectively overcomes the shortcomings of traditional single heat dissipation modes or simple dual-cooling superposition schemes, such as lag and coarse control. It achieves dynamic, directional, and precise enhanced heat dissipation for local hot spots that randomly appear inside the battery pack or are located in the heat exchange weak areas, significantly improving heat dissipation efficiency, temperature uniformity, and system safety redundancy. Attached Figure Description

[0018] Figure 1 This is a block diagram of the overall system structure in an embodiment of the present invention; Figure 2 This is a block diagram of the overall system structure in an embodiment of the present invention; Figure 3 This is a block diagram of the system's working state in an embodiment of the present invention.

[0019] Explanation of reference numerals in the attached figures: 1. Heat dissipation chamber; 2. First air inlet; 3. Second air inlet; 4. Exhaust vent; 5. Air guide plate; 6. Liquid cooling plate; 7. Liquid cooling channel; 8. Liquid cooling circulation pump; 9. Heat dissipation fin array. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0021] Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of this invention.

[0022] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0023] See Figures 1 to 3As shown, in order to achieve dynamic, directional, and precise enhanced heat dissipation for randomly occurring or weakly heated local hot spots within the battery pack, thereby improving heat dissipation efficiency, temperature uniformity, and system safety redundancy, this embodiment provides an energy storage battery pack heat dissipation system, including a heat dissipation chamber 1 and liquid cooling components, air cooling components, and an intelligent control unit disposed within the heat dissipation chamber 1. The heat dissipation chamber 1 is a rectangular cavity structure for housing the battery pack, made of polypropylene. A first air inlet 2 and a second air inlet 3 are respectively provided on opposite side walls of the heat dissipation chamber 1, and an exhaust vent 4 is provided on the side wall between the first air inlet 2 and the second air inlet 3. The liquid cooling components include a liquid cooling circulation pump 8, a liquid cooling plate 6, and a serpentine liquid cooling channel 7 coiled inside the liquid cooling plate 6. The liquid-cooled flow channel 7 is an aluminum serpentine pipe, using lightweight, high-thermal-conductivity aluminum flat tubes with a wall thickness of 0.9mm~1.1mm. This reduces thermal resistance and improves heat exchange efficiency while ensuring pressure-bearing reliability. The inner diameter is 3.8mm~4.2mm, increasing the coolant flow velocity and enhancing the convective heat transfer coefficient at a given pumping power. The pipe bending radius is ≥10mm, effectively reducing local flow resistance and pressure drop, avoiding dead zones or eddies caused by sharp bends, and ensuring uniform coolant flow distribution and hydraulic stability of the system. The liquid-cooled plate 6 is located near the top or bottom wall of the heat dissipation chamber 1 and fixed thereto by a bracket. The liquid-cooled plate 6 is parallel to the bottom or top wall of the heat dissipation chamber 1, and one side of the liquid-cooled plate 6 is in contact with the battery pack. The liquid-cooled circulation pump 8 is fixed to the outer wall of the heat dissipation chamber 1 or placed outside the heat dissipation chamber 1. Its outlet and inlet are connected in series with the liquid cooling channel 7 through connecting pipes to form a coolant circulation loop. Specifically, the outlet of the liquid cooling circulation pump 8 is connected to the inlet of the liquid cooling channel 7, and the inlet of the liquid cooling circulation pump 8 is connected to the outlet of the liquid cooling channel 7. Thus, the liquid cooling medium is continuously transported to the serpentine liquid cooling channel 7 in the liquid cooling plate 6 through the liquid cooling circulation pump 8 in an external circulation manner.

[0024] Furthermore, to improve heat dissipation, a heat dissipation fin array 9 is fixed between the liquid cooling plate 6 and the bottom or top wall of the heat dissipation chamber 1. The heat dissipation fin array 9 is arranged in a circular or linear array, and the liquid cooling plate 6 is in contact with the heat dissipation fin array 9. The heat dissipation fins are made of aluminum, and the air cooling channel, air guide plate 5, and heat dissipation fins together form a composite airflow channel, which can effectively improve heat dissipation efficiency.

[0025] Furthermore, the air-cooling assembly includes fans, air guide plates 5, and a drive mechanism. There are at least three fans, each fixed to one of the three continuous side walls of the heat dissipation chamber 1. Preferably, there are three fans: two fans are positioned opposite each other to supply air into the heat dissipation chamber 1, specifically installed at the first air inlet 2 and the second air inlet 3 of the heat dissipation chamber 1; the third fan is used to exhaust hot air from the heat dissipation chamber 1 and is installed at the exhaust outlet 4 of the heat dissipation chamber 1. The three fans form a dual-inlet, single-outlet air-cooling flow channel within the heat dissipation chamber 1, meaning the airflow of the heat dissipation chamber 1 adopts a "dual-inlet, single-outlet" structure with dual air inlets on both sides and a single air outlet at the back. The air-cooling channel connects to the air duct that runs through the battery pack casing. Two sets of air guide vanes 5 are respectively installed at the two air inlets of the air-cooling channel, near the two fans used for air supply. Each set of air guide vanes 5 is equipped with a corresponding drive mechanism, which is fixed to the heat dissipation chamber 1. The output of each drive mechanism is connected to each air guide vane 5 in its corresponding air guide vane array to adjust the angle of the air guide vane 5. The air guide vane array includes at least one row of multiple air guide vanes 5 arranged linearly along the width of the heat dissipation chamber 1. The corresponding drive mechanism includes at least one stepper motor and one rotating rod. The stepper motor is fixed to the casing of the heat dissipation chamber 1, and its main shaft passes through the heat dissipation chamber 1 and is coaxially fixed to the rotating rod. Multiple air guide vanes 5 are fixed to the rotating rod, and the stepper motor drives the rotating rod to adjust the angle of the air guide vanes 5. Preferably, the air guide vane array can also have multiple rows, and the drive mechanism uses a motor, gear set, and multiple rotating rods to adjust the angle of multiple rows of air guide vanes 5.

[0026] Based on the above structural configuration, the heat dissipation mode of this system is as follows: Air-cooled path: outside cold air → air-cooled air inlet channel → dual-cooled heat dissipation chamber 1 → air-cooled air outlet channel → exhaust port 4.

[0027] Liquid cooling path: Heat generated by the battery pack → Liquid cooling plate 6 → Coolant → Liquid cooling serpentine piping → Heat dissipation chamber 1 → External cooling circuit (external cooling is achieved through liquid cooling circulation pump 8 or an additional cooling system) The above structure enables air cooling and liquid cooling to be coupled and exchange heat within the same heat dissipation chamber 1, providing a physical basis for subsequent coordinated control and variable airflow adjustment.

[0028] Furthermore, the intelligent control unit includes a temperature sensing module, a battery heat dissipation main control module, and an execution control module connected in sequence. The temperature sensing module is used to collect the temperature of multiple high-risk areas within the battery pack, the inlet and outlet temperatures of the liquid cooling medium within the liquid cooling plate 6, and the ambient temperature. To accurately acquire temperature parameters, the temperature sensing module includes: multiple hot spot temperature sensors arranged near the top terminals of the battery cells, the side of the central battery cells in the module, the busbar crimping interface, and the root of the tabs within the battery pack, used to collect the temperature of multiple high-risk areas within the battery pack; temperature sensors arranged at the air inlet and outlet of the air-cooling channel, wherein the air inlet temperature sensor also characterizes the ambient temperature; and temperature sensors arranged at the liquid inlet and outlet of the liquid cooling plate 6, used to collect the inlet and outlet temperatures of the liquid cooling medium within the liquid cooling plate 6. The battery heat dissipation main control module is used to identify hot spots and determine heat dissipation control strategies based on the temperature of high-risk areas, the inlet and outlet temperatures of the liquid cooling medium in the liquid cooling plate 6, and the ambient temperature. The execution control module is electrically connected to the drive mechanism, the liquid cooling circulation pump 8, and the fan, and is used to dynamically adjust the fan speed, the flow rate of the liquid cooling circulation pump 8, and the angle of the air guide plate 5 according to the heat dissipation control strategy to achieve directional heat dissipation.

[0029] Specifically, the structure of the intelligent control unit is shown in detail below (see...). Figure 2 and Figure 3 (as shown) (a) Information perception 1. Composition of the temperature sensing module (1) Duct temperature sensor, used for wind-side energy efficiency monitoring; 1) Surface mount temperature transmitters are selected and fixed to the air inlet and outlet of the air-cooled duct with clips. Specifically, one of the duct temperature sensors is installed on the inner wall of the heat dissipation chamber near any of the fans used for air supply to monitor the inlet air temperature of the air-cooled duct. T 1. The air duct temperature sensor is installed on the inner wall of the heat dissipation chamber near the exhaust fan to monitor the exhaust air temperature of the air-cooled airflow duct. T 2;

[0030] 2) The probe of the duct sensor is arranged perpendicular to the wind direction to avoid mechanical vibration and loosening caused by the forward impact of the airflow, and to ensure long-term measurement stability; 3) Inlet air temperature T 1. Also used to characterize ambient air temperature T A It is used for environmental correction of the wind turbine foundation speed.

[0031] (2) Battery pack hotspot temperature sensor T a / T b / T c / T d ), used to monitor the temperature of high-risk areas for thermal runaway within the battery pack, as shown in Table 1; Table 1. Temperature Monitoring Configuration for High-Risk Areas of Thermal Runaway Inside the Battery Pack , The contact pressure between the sensor probe and the measured surface is ≥5N to reduce contact thermal resistance and improve temperature response speed and measurement accuracy.

[0032] (3) Liquid cooling plate inlet and outlet liquid cooling temperature sensors are used to monitor the coolant temperature and liquid-side heat exchange effect.

[0033] 1) Installed at the inlet and outlet of the liquid cooling channel inside the liquid cooling plate, respectively, to collect the inlet temperature of the coolant (liquid cooling medium) in the liquid cooling channel in real time. T 6 and outlet temperature T 7; 2) T 7– T A temperature difference of 6 is used to evaluate the liquid-side heat transfer effect and determine whether the liquid cooling participation is sufficient under the current operating conditions.

[0034] The sensor output signals are fed into the signal conditioning circuit of the signal processing module. Each analog signal first passes through an RC low-pass filter circuit with a cutoff frequency of 10Hz to filter out high-frequency electromagnetic interference in the vehicle environment. Then, the signal is amplified to the 0V~5V range by an instrumentation amplifier. Finally, it is converted into a digital quantity by a 12-bit A / D converter with a sampling frequency of 10Hz and transmitted to the battery cooling main control module via the SPI interface. The SPI interface is used for short-distance high-speed data transmission between the signal processing module and the battery cooling main control module, while the CAN bus is used for system-level communication and status interaction between the battery cooling main control module and various functional modules.

[0035] (ii) Decision control The decision control layer uses a TI TMS570 automotive-grade MCU as the core processor of the battery heat dissipation main control module. The MCU has approximately 1MB of built-in Flash memory for storing heat dissipation strategy algorithms and historical temperature data. The battery heat dissipation main control module interacts with the signal processing module and the execution control module via a CAN bus to form a closed-loop control. The decision control mainly includes hotspot identification and location, fuzzy PID hierarchical regulation, precise airflow direction control under hotspot sub-conditions, and pre-regulation prediction and fault fallback.

[0036] 1. Hotspot identification and location The battery heat dissipation main control module includes a hotspot identification unit, used for... Ta / Tb / Tc / TdThe system collects temperature data from high-risk areas of the battery pack and analyzes it in real time. When a certain area's temperature is ≥ 38℃ or its temperature rise rate is ≥ 0.05℃ / s, the system automatically identifies that area as a "hotspot area" and locates its coordinates based on the spatial arrangement of the sensors. Through this hotspot identification unit, the system can identify potential hotspots in the early stages of thermal runaway, providing target guidance for subsequent targeted heat dissipation.

[0037] 2. Fuzzy PID hierarchical decision making The battery heat dissipation main control module includes a graded operating condition control unit. In this invention, the graded operating condition control unit combines coupling coefficients and multiple temperature thresholds to divide the system operating conditions into three levels. Fuzzy rules are used to adjust PID parameters or outputs, ensuring that the fan speed and liquid cooling flow rate continuously change with temperature deviation and rate of change, avoiding oscillations and energy waste caused by simple on / off control. The unit triggers the switching between the three operating conditions by combining coupling coefficients and temperature thresholds. Simultaneously, based on the fan speed formula and liquid cooling flow rate formula, basic operating parameters are calculated to ensure the accuracy and quantification of operating condition matching.

[0038] Fan speed regulation formula: , in, The duty cycle represents the fan speed. The value range is 30% to 100%. The ambient temperature is monitored by a duct temperature sensor at the air inlet of the air-cooled duct, which represents the inlet air temperature of the air-cooled duct. T 1. Normalization correction is performed based on 25℃ to avoid insufficient heat dissipation in high-temperature environments and energy waste in low-temperature environments. This is the environmental temperature regulation weighting coefficient, with a value range of 0.5% / ℃ to 2% / ℃. This is the highest temperature of the battery pack, which is the maximum temperature collected in real time by multiple hot spot temperature sensors deployed inside the battery pack.

[0039] Of this, 30% is the duty cycle for the minimum safe operating speed of the wind turbine. At ≥100%, full-speed operation is achieved. When the duty cycle is ≤30%, the rated speed is operated at the duty cycle corresponding to 30%.

[0040] The formula for regulating the flow rate of a liquid-cooled circulating pump is as follows: , in, This refers to the duty cycle of the flow control signal for the liquid-cooled circulating pump, which physically corresponds to a percentage of the pump's rated flow rate. A 50% duty cycle represents the minimum safe operating flow rate for the liquid-cooled circulating pump. FWhen ≥100%, the liquid-cooled circulating pump operates at full flow; when F When the flow rate is ≤50%, the system operates at the rated flow rate corresponding to a 50% duty cycle of the liquid cooling circulating pump flow control signal. Under Level 1 operating conditions, the liquid cooling subsystem is shut down or in standby mode. F Set to 0%.

[0041] See Figure 3 As shown, the system's operating conditions are divided into three levels: 1) Level 1 operating condition (low temperature and low load): T max ≤35℃ and T 7– T When 6 < 3℃, F = 0%, control the liquid cooling circulation pump to shut down or standby, and control the fan to run at the rated speed with a duty cycle of not less than 30%, so as to maintain the basic heat dissipation capacity with low energy consumption.

[0042] 2) Level II operating condition: 35℃≤ T max ≤45℃ and 3℃≤ T 7– T 6 < 5℃, control the liquid cooling circulating pump to operate at the rated flow rate with a flow control signal duty cycle of not less than 50%, and control the fan to operate at the rated speed with a speed duty cycle of not less than 50%, so as to make up for the problem of insufficient efficiency of single air cooling and improve the overall heat exchange capacity.

[0043] 3) Level 3 operating condition (high temperature and high load): T max ≥45℃ and T 7– T When the temperature is ≥5℃, the fan is controlled to run at full speed, and the liquid-cooled circulating pump is controlled to run at full flow. Both air cooling and liquid cooling are in enhanced heat dissipation mode to maximize heat dissipation capacity. Simultaneously, a buffer zone is set between the secondary and tertiary operating conditions, meaning that temperature changes must be maintained for at least 30 seconds. T max Switch to a higher level only when the temperature rises by 1°C to avoid frequent switching of operating conditions.

[0044] 3. Hotspot Level 3 Sub-condition and Air Guide Plate Control In satisfying T maxWhen the temperature reaches ≥ 45℃ and the corresponding single-point temperature rise rate is ≥ 0.1℃ / s, the system enters the local hotspot level three sub-condition. This sub-condition is a local fine-control mode running in parallel with the main level three condition. Its control strategy is as follows: the liquid cooling flow rate remains unchanged under the current main condition, without significant disturbance to the liquid cooling path; the fan operates at a speed corresponding to approximately 80% of its duty cycle, balancing heat dissipation capacity and energy consumption; only the guide vane angle is adjusted, precisely within the range of 0°~180°, generating an asymmetric airflow field to distribute more cold air to the weak heat exchange area where the hotspot is located, appropriately reducing the airflow distribution weight in non-hotspot areas, and ensuring that the cold air impacts the surface of the weak heat exchange area as vertically as possible. The guide vane angle θ is determined by... , , , The temperature and its gradient are calculated in real time with weights. For example:

[0045] , , , , (1) Single hotspot scenario: when only T a The maximum temperature in the hotspot area meets And when the main focus is on a hot topic, the following can be used: , in, This refers to the deflection angle of the air guide plate; For the corresponding T a The maximum temperature in the hotspot area; 30° is the initial angle corresponding to a base temperature of 40°C, representing a uniform airflow distribution state. This is the angle gain coefficient. When... hour, ;when hour, As the temperature continues to rise, the deflection angle increases linearly, but does not exceed the mechanical limit angle of the air guide plate. 40℃ is the reference temperature for the angle, which is different from the hot spot temperature. When the temperature is between 38℃ and 40℃, the system has identified the hot spot, but the air guide plate remains in its initial position (30°), relying solely on basic heat dissipation. Between 40℃ and 45℃, the air guide plate begins to deflect linearly, and the airflow becomes more concentrated as the temperature increases. When the temperature is ≥45℃, it enters a high-risk zone, and the weight increases quadratically, prioritizing response.

[0046] (2) Dual hotspot scenarios (e.g.) T a , T b (Also a hotspot area) , in, , , , , In the formula, in the formula, The deflection angle of the air guide plate. and Used to highlight areas with higher temperatures and greater risks. In the formula, , These are the theoretical deflection angles when considering only a single hotspot. , The risk weight is calculated based on the square of the difference between the temperatures exceeding the risk threshold of 45°C. Through this weighted calculation, the system can prioritize responding to areas with higher temperatures and greater risks when multiple hotspots coexist, thereby optimizing the allocation of cooling airflow.

[0047] (3) Three hotspot scenarios (e.g.) T a , T b , T c (Also a hot topic) , , in, The deflection angle of the air guide plate, weight , , This is used to highlight areas with higher temperatures and greater risks. , , These are the theoretical deflection angles when only a single hotspot is considered.

[0048] (4) Multi-hotspot scenario: Based on the temperature rise rate of each hotspot, prioritize the area with the fastest temperature rise rate for centralized wind direction control. When the hotspot temperature drops below 42℃ and remains below 42℃ for more than 10 seconds, exit the hotspot level 3 sub-condition to avoid frequent wind direction switching.

[0049] 4. Predicted temperature and dynamic threshold adjustment The safe temperature threshold for hotspot areas is dynamically adjusted based on the rate of temperature rise, and future temperature predictions are used to further optimize the system. As a basis for switching operating conditions, it enables advance control rather than reactive response.

[0050] , in, To predict temperature; The current temperature of the hotspot area; The preset prediction time step (e.g., 1s~2s) is used. The rate of change of temperature over time, or the rate of temperature rise, represents the increase in temperature per unit time and is a core parameter reflecting how quickly the system's temperature rises. If... A high temperature indicates that the system may quickly reach or exceed the set safe temperature of 45℃. Therefore, the safe threshold can be lowered from 45℃ to 43℃ in advance. The lower temperature and relatively slow temperature changes allow for a safety threshold of 46°C, reducing unnecessary intervention. If... If so, the operating condition level should be upgraded in advance.

[0051] 5. Sensor fault compensation module When any temperature sensor in the temperature sensing module detects a fault (such as an open circuit, short circuit, or abnormal value), the battery heat dissipation main control module estimates the temperature based on the temperature data of the effective temperature sensor adjacent to the faulty temperature sensor, as well as the current deflection angle of the air guide plate and the inlet and outlet temperatures of the liquid cooling medium on the liquid cooling plate. This is done to compensate for the temperature data of the faulty temperature sensor and continue to execute the heat dissipation control strategy to avoid safety risks caused by hot spot misjudgment.

[0052] (III) Decision Implementation The execution control module is connected to the air-cooled and liquid-cooled components. Based on the parameters such as the target fan speed, liquid cooling flow rate, liquid cooling valve opening, and air guide plate angle issued by the battery heat dissipation main control module, it completes specific execution actions.

[0053] 1. Wind direction adjustment and air guide plate drive The fan uses a 120CFM brushless DC fan, and the control module outputs a PWM signal (duty cycle 0%~100%) to adjust the speed, with a speed adjustment response time ≤200ms. When a hot spot appears in a weak area of ​​the liquid cooling plate heat exchange (such as a bend in a serpentine pipe or a narrow flow channel), the fan is activated, and the air guide plate is driven to precisely adjust its angle within the range of 0°~180°. Based on the hot spot location locked by the decision-making layer, an asymmetric airflow field is generated while reducing the airflow distribution weight in non-hot spot areas, allowing the cold air to blow vertically towards the weak heat exchange point and maximizing the utilization rate of the heat exchange surface. The air guide plate is controlled by a hybrid stepper motor M1 with a step angle of 1.8°. The air guide plate shaft is fixed to the inner wall of the air duct through bearings, realizing precise control of the airflow distribution ratio.

[0054] Through the aforementioned wind direction adjustment, when hot spots appear in a localized area of ​​the battery pack, the system can quickly construct an asymmetric wind direction field inside the heat dissipation chamber, causing the cold air to focus on impacting the hot spots and the weak heat exchange areas they are located in, reducing the air volume distribution in non-hot spot areas, and avoiding waste of cooling capacity.

[0055] 2. Fan speed and liquid cooling flow rate adjustment Based on the fan speed and liquid cooling flow rate parameters calculated by the decision control algorithm, the execution control module adjusts the air-cooled fan speed, liquid cooling circulation pump flow rate, and liquid cooling valve opening via PWM signals to match the coupling coefficient of the air-side and liquid-side operating parameters, forming a synergistic heat exchange gain. The liquid cooling circulation pump is a miniature diaphragm pump with a rated flow rate of 5L / min, and the execution control module adjusts the pump speed via PWM signals. The liquid cooling valve is a 2mm diameter electromagnetic proportional valve, with its opening controlled by a 0V~24V current signal and a response time ≤500ms. The serpentine liquid cooling channel uses aluminum flat tubes with a wall thickness of 1mm and an inner diameter of 4mm, fixed in the dual-cooling heat dissipation chamber by brazing. The pipe bending radius is ≥10mm to avoid excessive coolant flow resistance. The liquid cooling plate is made of die-cast aluminum, with grooves machined on the surface to match the bottom of the battery pack. Thermal grease is applied to the grooves, and the plate is secured to the battery pack with bolts.

[0056] Through the aforementioned joint adjustment, the operating parameters of the wind-side and liquid-side are made to meet the preset coupling coefficient relationship, forming a synergistic heat exchange gain: under low-load conditions, air cooling is the main mode, with liquid cooling as a supplement or in standby mode; under high-load hotspot conditions, both air cooling and liquid cooling enter an enhanced mode, and the airflow direction is dynamically adjusted according to the local hotspot situation, realizing a synergistic control strategy of "macro-level operating conditions + fine-tuning of local hotspots". In summary, this invention integrates liquid cooling and air cooling at the structural level and introduces graded precise control and variable-direction directional air distribution at the control level, achieving synergistic enhanced heat exchange under fixed water circuit conditions. This effectively eliminates hotspots inside the battery pack, providing core technical support for the safe, efficient, and stable operation of energy storage power station battery packs.

[0057] Based on the above system design, the core steps of this invention for battery pack heat dissipation can be summarized as follows: The temperature sensing module collects the temperature of high-risk areas within the battery pack, the temperature of the liquid cooling medium entering and exiting the liquid cooling plate, and the ambient temperature.

[0058] Based on the temperature of high-risk areas within the battery pack, the distribution of hotspot areas in the battery pack is determined, and their spatial locations are pinpointed.

[0059] Based on the highest temperature of all hot spots in the battery pack and the temperature difference between the inlet and outlet of the liquid cooling medium on the liquid cooling plate, a heat dissipation control strategy is determined.

[0060] Based on the heat dissipation control strategy, the fan, liquid cooling circulation pump, and drive mechanism are started to dynamically adjust the fan speed, liquid cooling circulation pump flow rate, and air guide plate angle. When the identified hot spot area appears in a local location of the battery pack, the current liquid cooling circulation pump flow rate is maintained, the fan is controlled to run at a preset speed, and the angle of the air guide plates on both sides of the air cooling channel is adjusted to form an asymmetric airflow field, which directs the cooling airflow to the hot spot area to complete the directional heat dissipation of the battery pack.

[0061] Furthermore, it also includes predictive control steps: based on the current temperature and rate of temperature rise in the hotspot area, predicting future... The temperature after a certain time is determined, and the threshold for the operating condition classification is dynamically adjusted or enhanced heat dissipation is triggered in advance based on the predicted temperature.

[0062] In summary, this invention uses a temperature sensing module to collect real-time data on the temperatures of multiple high-risk areas within the battery pack, as well as the temperature of the liquid cooling medium and the ambient temperature. The battery heat dissipation main control module identifies hot spots and determines heat dissipation control strategies. Then, the execution control module dynamically and collaboratively adjusts the fan speed, liquid cooling circulation pump flow rate, and the angle of the adjustable air guide plate in the air-cooling channel. This organically integrates and intelligently distributes the air-cooled airflow organization with the fixed liquid cooling water path within the heat dissipation chamber. The system can dynamically adjust the overall cooling intensity and precisely control the airflow direction based on the real and random temperature field changes inside the battery pack. In particular, for weak heat exchange areas caused by the fixed liquid cooling channel, the air guide plate can form an asymmetric airflow field, directing the cooling airflow to local hot spots. This system effectively overcomes the shortcomings of traditional single heat dissipation modes or simple dual-cooling superposition schemes, such as lag and coarse control. It achieves dynamic, directional, and precise enhanced heat dissipation for local hot spots that randomly appear inside the battery pack or are located in weak heat exchange areas, significantly improving heat dissipation efficiency, temperature uniformity, and system safety redundancy.

[0063] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A heat dissipation system for an energy storage battery pack, comprising a heat dissipation chamber for housing the battery pack, characterized in that, Also includes: The liquid cooling assembly includes a liquid cooling circulation pump, a liquid cooling plate, and a liquid cooling channel coiled in a serpentine pattern inside the liquid cooling plate. The liquid cooling plate is located near and fixed to the top or bottom wall of the heat dissipation chamber, and one side of it is designed to contact the battery pack. The outlet of the liquid cooling circulation pump is connected to the inlet of the liquid cooling channel, and the inlet of the liquid cooling circulation pump is connected to the outlet of the liquid cooling channel, forming a coolant circulation loop. The air-cooled assembly includes fans, air guide plates, and drive mechanisms. There are at least three fans, which are fixed on three continuous side walls of the heat dissipation chamber. Two fans are arranged opposite each other to supply air into the heat dissipation chamber, and the other fan is used to exhaust hot air from the heat dissipation chamber. The three fans form a dual-inlet, single-outlet air-cooling channel in the heat dissipation chamber. The air-cooling channel is used to connect with the air duct that runs through the battery pack casing. Two sets of air guide plate arrays are respectively arranged on the side of the air-cooling channel near the two fans used for supplying air. Each set of air guide plate arrays is equipped with a drive mechanism corresponding to it. The drive mechanism is fixed on the heat dissipation chamber. The output end of each drive mechanism is connected to each air guide plate in the corresponding air guide plate array to adjust the angle of the air guide plate. The intelligent control unit includes a temperature sensing module, a battery heat dissipation main control module, and an execution control module that are connected in sequence. The temperature sensing module is used to collect the temperature of multiple high-risk areas in the battery pack, the inlet and outlet temperature of the liquid cooling medium in the liquid cooling plate, and the ambient temperature. The battery heat dissipation main control module is used to identify hot spots and determine heat dissipation control strategies based on the temperature of high-risk areas, the inlet and outlet temperatures of the liquid cooling medium in the liquid cooling plate, and the ambient temperature. The execution control module is electrically connected to the drive mechanism, the liquid cooling circulation pump, and the fan, and is used to dynamically adjust the fan speed, the liquid cooling circulation pump flow rate, and the air guide plate angle according to the heat dissipation control strategy to achieve directional heat dissipation.

2. The heat dissipation system for an energy storage battery pack according to claim 1, characterized in that, A heat dissipation fin array is fixed between the liquid cooling plate and the bottom or top wall of the heat dissipation chamber, and the liquid cooling plate is in contact with the heat dissipation fin array.

3. The heat dissipation system for an energy storage battery pack according to claim 1, characterized in that, The temperature sensing module includes: Multiple hotspot temperature sensors are arranged next to the terminal posts of the cell top cover, the side of the cell in the center of the module, the bus crimping interface, and the root of the tab in the battery pack to collect the temperature of multiple high-risk areas in the battery pack. The air duct temperature sensor is installed at the air inlet and air outlet of the air-cooled flow channel to monitor the air inlet temperature and exhaust temperature of the air-cooled flow channel. The air inlet temperature is also used to characterize the ambient temperature. Liquid cooling temperature sensors are placed at the inlet and outlet of the liquid cooling plate to collect the inlet and outlet temperatures of the liquid cooling medium on the liquid cooling plate.

4. The heat dissipation system for an energy storage battery pack according to claim 1, characterized in that, The battery heat dissipation main control module includes a hot spot identification unit. The hot spot identification unit is used to determine that the area corresponding to any of the temperature measuring terminals is a hot spot area when the temperature value collected by any of the temperature measuring terminals is ≥38℃ or its temperature rise rate is ≥0.05℃ / s, and to lock the hot spot coordinates according to the spatial position relationship of the sensors.

5. The heat dissipation system for an energy storage battery pack according to claim 3, characterized in that, The battery heat dissipation main control module includes a graded operating condition control unit, which is used to perform the following operations: Level 1 operating condition: When the battery pack reaches its highest temperature T max When the temperature is ≤35℃ and the temperature difference between the inlet and outlet of the liquid cooling medium on the liquid cooling plate is <3℃, the liquid cooling circulation pump is controlled to be shut down or put into standby mode, and the fan is controlled to run at the rated speed with a duty cycle of not less than 30%. Level 2 operating condition: When 35℃ ≤ maximum battery pack temperature T max When the temperature of the liquid cooling medium is ≤45℃ and the temperature difference between the inlet and outlet of the liquid cooling plate is ≤5℃, the liquid cooling circulating pump is controlled to operate at the rated flow rate with a flow control signal duty cycle of not less than 50%, and the fan is controlled to operate at the rated speed with a speed duty cycle of not less than 50%. Level 3 operating condition: When the battery pack reaches its highest temperature T max When the temperature is ≥45℃ and the temperature difference between the inlet and outlet of the liquid cooling medium is ≥5℃, the fan is controlled to run at full speed and the liquid cooling circulation pump is controlled to run at full flow. Among them, the highest temperature of the battery pack T max This refers to the maximum temperature collected in real time by multiple hotspot temperature sensors deployed within the battery pack.

6. The heat dissipation system for an energy storage battery pack according to claim 3, characterized in that, The fan speed and the liquid cooling circulation pump flow rate are determined according to the following formulas: Fan speed regulation formula: ， in, The duty cycle represents the fan speed. The value range is 30% to 100%; Ambient temperature; This is the highest temperature of the battery pack, which is the maximum temperature collected in real time by multiple hot spot temperature sensors deployed inside the battery pack. The environmental temperature regulation weighting coefficient has a value range of 0.5% / ℃ to 2% / ℃. The formula for regulating the flow rate of a liquid-cooled circulating pump is as follows: ， in, Duty cycle of the flow control signal for the liquid-cooled circulating pump; This refers to the liquid inlet temperature of the liquid cooling plate. This refers to the liquid outlet temperature of the liquid cooling plate.

7. The heat dissipation system for an energy storage battery pack according to claim 3, characterized in that, It also includes a sensor fault compensation module, which is used to estimate the temperature when any temperature sensor in the temperature sensing module fails, based on the temperature data of the effective temperature sensor adjacent to the failed temperature sensor, as well as the current deflection angle of the air guide plate and the inlet and outlet temperatures of the liquid cooling medium on the liquid cooling plate, so as to compensate the temperature data of the failed temperature sensor and continue to execute the heat dissipation control strategy.

8. A heat dissipation method for an energy storage battery pack, implemented according to a system as described in any one of claims 1-6, characterized in that, Includes the following steps: The temperature sensing module collects the temperature of high-risk areas inside the battery pack, the temperature of the liquid cooling medium entering and exiting the liquid cooling plate, and the ambient temperature. Based on the temperature of high-risk areas within the battery pack, the distribution of hotspot areas in the battery pack is determined, and their spatial locations are pinpointed. Based on the highest temperature of all hot spots in the battery pack and the temperature difference between the inlet and outlet of the liquid cooling medium on the liquid cooling plate, a heat dissipation control strategy is determined. Based on the heat dissipation control strategy, the fan, liquid cooling circulation pump, and drive mechanism are started to dynamically adjust the fan speed, liquid cooling circulation pump flow rate, and air guide plate angle. When the identified hot spot area appears in a local location of the battery pack, the current liquid cooling circulation pump flow rate is maintained, the fan is controlled to run at a preset speed, and the angle of the air guide plates on both sides of the air cooling channel is adjusted to form an asymmetric airflow field, which directs the cooling airflow to the hot spot area to complete the directional heat dissipation of the battery pack.

9. A heat dissipation method for an energy storage battery pack according to claim 7, characterized in that, It also includes predictive control steps: based on the current temperature and rate of temperature rise in the hotspot area, predicting future... The temperature after a certain time is determined, and the threshold for the operating condition classification is dynamically adjusted or the enhanced heat dissipation action is triggered in advance based on the predicted temperature, wherein the predicted temperature is determined according to the following formula: ， in, To predict temperature; The current temperature of the hotspot area; This is the preset prediction time step.

10. The heat dissipation system and method for an energy storage battery pack according to claim 1, characterized in that, The method for adjusting the angle of the air guide plate is as follows: For a single hotspot area, the deflection angle of the air guide plate is determined according to the following formula: ， in, This refers to the deflection angle of the air guide plate; This represents the maximum temperature in the corresponding hotspot area; For multiple hot spots, the deflection angle of the air guide plate is the weighted average of the deflection angles of the air guide plate calculated for each hot spot.

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